Apparatus for burning liquid fuel



W. E. EVVING APPARATUS FOR BURNING LIQUID FUEL Filed sepa?, 1923 3sheeis-Shee 2 N y l Patented Mar. 12.1925. i

UNI-'rse `Sfrn'rss-` PATsi'vrr." joFFicE.

WILLIAM n. lawine, or PEoeIA, ILLIrIoIsl `API* electrics Fon BURNINGLIQUID FUEL.

- Applicatie@ ma setember fr, 192s. seran No. 651,374.

"reference inarked thereon, which forni a part of this sl'iecification'.

The apparatus disclosed herein is of the general type disclosed ininy'copending ap plicationfor; U: Letters Patent, tiledA Mai-ch e, 1922,stri-n No'. stoner).

This invent-ion relatesto an improved liquid fuel house heatingr burneradapted for use in connection with hot air-furnaces, boilers andcommercial furnaces, and constructediwith a minimum of fuel valves andadapted to 4viv-'e Va continuous fire, the-Vol'- urne offvvhich isvariableat the \villof an operator,without retluiriiigthe operator toknow themechanical `nature of the-apparatus.

It is an object of this invention to provide a liquid fuel burnerconstructed to avoid heating,r of the fuel alonebe't'ore it reaches thefuel nozzle, thereby eliminating dist'il 4lation of the fuel.

It is also an object of:v the. invention to' 4`provide a liquid fuelburner adapted to'us'e forced draft and low: pressure fuel feed'thusallowing for exact proportioning ofv fuel and air under all conditionsoffvveather, resulting in the complete combustion of the" fuel and theelimination ofnvaste.

Another object of the invention is the?y fuel burner which ispractically noiseless and comparatively odorless both as to dripping oiland as'to` eon'ibustion fumesf l It is furthermore an object of thisinvention 'to provide an `improved 'liquid fuel household burner ofsimple and inexpensivev construction adapted to be readilyr installedfor use 4in connection with any furnace'and using' the method ofinduetiug; fuel into an air 'stream b v passing .the air sticani througha Ventnri'tubi-` thereby lovverinrer the pres-` surebelow latmosplwrc.and drawing in rfuel vvhlchl is under atmospheric pressure, or' slightlyhigher. I

, Other and It an important object of this invention `to provide aliquid fuelv burner vwherein a are 'vapf-irized before passing into theburner grating. f

furtherl important objects of this invention will bel :tpparentfroin thedisclosures in the specification and accompany-- ing drawings.

This invention (in a' preferred forni) is illustrated lin the drawingsand hereinafter more fully described."

'On'- the dravvingsz- Y l AFigure l `is a top plan vien7 of a liquidfuel burner embodying the principles of this invention. i

Figure 2 is a side elevation thereof.

F injure- 3 iS an enlarged vertical detail section taken on line V3---3of Figure l.

` F igurc 4 is an enlarged detail section `taken online 4-4 of Figure.1.4

Figure 5 is an enlarg'edf fragmentary detail sectiontalten on lineofFigure l; Figure (S-isa plan viewof a modified type of liquid fuelburner for hotairand coinrnercial f furnaces vvhe're automatic controlis not needed, this one being manually. controlled. i

Figure 'i is a vertical sectional view taken on line 7 -7 of Figure G.

As'shoivn'on thevr drawingm; The dotted line 1 of Figures l and Q indi-Cates the front vvall ofa `furnace having a fire box door.

The liquid fuel burner of this invention i's'adapted for use inconnection with a household or'commercial furnace and isadaptc'd'tibeinounted on the esten riorat the 'front 'ofthe furnace with the Aburnergrating"`projectingv through the furnace fire -box door 'into the-,lirebox or through the ashpit door.'

The `improved' burner mechanism of this "invention comprises a mainelectric motor 2 connected to drive a main blower 3 which. is adapted toblow air into one end of an air duct or pipe 4. A control valve 5 ismounted on the blower 3 and adjustable by means' of `a lever or valvestein ti. It Venturi tube? is forrnedin the duct 4. fr liquid fuelnozzle 8 has the upper end there of projectinginto the Venturi tube. 7and. is controlled by a needle Valve 9. The nonn 4zie Sis connected to athree-way connector 10, lo which one en'd of a liquid fuel supply pipeor tube 11 isl connected leading fromv a y Vfuel tank 12. Liquid fuelflows lay-gravity' iii from thetank 12 through the tube 11 into theconnector 10 ,wh/ichisv` provided with a eut-off'ztalve'flr/ftonnectedto the tank 12 is a Afuel supply'pipeV 14 and an excess fuelretn'rnpipe15. The 'return pipe 15 serves tofinaintziinthe fuel oil in the tank 12.at a predetermined level represented by the dot .ted line/16 (Figure 4)the level of which is slightly below the. horizontal level ofthe outletend of the nozzle 8. An air pressure tube 17 has one end thereofconnected to thev top of the oil tank 12 for the'purpose `of 'givingslightly more thanatmospheric pres-l sure on the fuel to give a betterspray through the nozzle.

The' second end Vofthe air duct 4 projects through a casing or housing18 and is connected to a main or large vaporizer casing' 33. A. primaryo1" smaller Vaporizer casing i 19 of cylindrical shape closed at thetop` j and the bottom is mounted within the housing 18 below thevaporizer casing 33. Projecting into the b'ottom of the rimary vaporizer19, is a pi e stem 20 o a `primary grate 21 ofiannu ar shapeVhaving'burner openings 22therein -Th'c primary grate 21 draws-fuel fromthefvaporizer 19 and when burning serves to *'lieat the primaryvaporizer afterwhich the heat passesV through the housingvlS into thefurnace by Way of a largeflue or pipe'23L' The flue 2 3 is connected totheto'p of the housing 18 and pio- Vjects into the furnace through thelire box lor ash pit door. The inner end of the flue' 23 is o en .at 24(Figure 3).

As s own in Figure-3,'a preheat'er is provided witliin the lower portionof the housing 18 and lconsists of a grate or. gas burner 25 having a'as supply pipe 26 connected therewith.' T 'e housing 18 is provided withan opening 27 to permit lighting ofthe reheater burner 25 andthe grate21.y on'- x nected to the top of the primary vaporizer 19 is a pipe stem28 ofan annular secondary. or auxiliary grate 29 having burner openings30 in the top thereof adapted to permit fuel from the vaporizer 19toescape and be ignited.' An opening 31 is provided in the l housing 18 topermit lighting of the grate 29.

pinto the open end thereof where it is at-f tached to an elbow 35. Theelbow 35 pro- 24 (Figure 3) 'andlias formedon the projecting end there..

Mounted in the housing 1S above the secondary grate 29 is a mainvapoi'izer casing 33 of cylindrical shape. Connected to tlie top of themain vaporizer casing' 33 is a ipe 4 which projects through the' flue 23jects through the flue opening Y. of a burner casing 36 having seatedtherein 'a burner plate'o'r grating 38 having a plu#v rality lofburnefropenings therein.; Above the burner grate 36,*and close to it, is:i

strike plate provided with a plurality-*of concentric slots 3T. The'object of this' plate 37vis'to reduce the velocityof the. fuelinixtureto a point where itwill become ignited' and buin without blowing itselt'out, the flames issuing through the slots V37. burner 39, tittlngtightly in the centeiol the burner grate 3G, serves to` ignite' :thefuel mixture issuing therefrom. The pilot burner is supplied 4with fuelfrom the vaporizer 19 through a tube 40. j

As illustrated in Figure 1, a primary electric inotoi` 41 is provided todrive a primaryy blower 42 having a valve 45t-mounted thereon adapted tobe .controlled by a 'lever or valve stem 44. Connected to the primaryblower 42 to -receive air therefrom is a primary pipe or air duct 45having `a Venturi- 'tube 4G therein. The A`air duct 45 projects into thehousing 18 and is conneete'dito thc primary vaporizer 19'to supply thesame with fuel. The air pressure tube 17 is connected to the air duet 45between the. blower `42 and theVenturi tube'46. j V

Projecting into the Venturi tube 46 is the upper end: of aliquid `fuelnozzle 4T controlled bv 'a needle valve operable by theA valve stein1148. 'llie nozzle 47. is connected to a three-ivfay connector 49 (Figure2) having a eutott' valve 5 0 in the middle ai'in thereof. The ends ofthe nozzles S and 47 are on the same horizontal level.. Connected ,ttothe middle arm of the connector 49 is oneyend of a fuel pipe 51, theother end of which projects into the fuel tank 12.

Figures 6 and 7 illustrate a. moditied form ofa liquid fuel burner of amultiple type for use in connection with .hot air und com-- nected withthe tank 59 to maintain the` level of fuel in the tank at apredetermined height slightly below the levelof the nozzles. A pipe 62connects the tank 59 with a 'valve controlled nozzle G3, the end ofwhich project'sfinto the 'Venturi tube 5T. The nozzle is provided with ashut-oli' valve 64. j Connectedto'each of the seeondai blowers y54 is anair duct 65 ha ingir a. 7'enturi tube 66 and also provided with a valve67 betweenI the respective blower 54 A. 'pilot control and the Venturi.tube 66. Each Venturi 'tube'v '6G-lis provided with a nozzle similar tothe nozzle (and said nozzle'is connected with the fuel tank 59 by a pipe68. Each nozzle is provided witha shutoffY valve.

'l` he duct 56 projects into a Acasing or lions? ing 69 having a flue7U. which 1s 'ai'.hi'ptcil to project into the doorofa furnace, The duct.'36 is connected to 4a primary vaporizcr casing 7l Projcetingmtothe'bottoni of the vaporizcr casing 71 is'aprpe stein of a-pri- Vmarygrate 72 having a seriesl of buiner A. furnace by. Wayof vthe flue 70.

.A prebeater isprovided in the 'lower part of thehousing 69 and consistsof an apertured grate. 73. having a gas supply pipe 7 4 connectedtherewith. 4

Connected to the vaporizer `71 is lan. auxiliary grate 75". A pipe 75.is connected to .the grate 75 and projects upwardly in the housing 69andis closed at its upper end.

f Connected at intervalsi'inthe stand pipe A75 are. a plurality: ofvapertured horizontal branch .pipes 76, each o which is 'positioned.runder a secondary vvalfiorizer p casing 77 .mounted within the housing69one above the other. /Each of these pipes 76l has a series .of burneropenings, each pipe'76 serving asa burnerto heat thevaporizer ,abovc'The four pipes 78 pro'ect through the flue. 70 and into` the lire. oxqofthe furnace.l

i sie.

. shortl whi 19 and all thev other metal parts', the pri i'i1ary' motor41 is then started and acts to operate it. The ducts'65 project iiitothe housing 69 and. are connected witlrthe respective vafporizers 77.Attached to the top of cuch vaporizer. 77 is one end ofl a burner pipe78.

Each pi 78 has a burner lgrate 7 9 secured thereto. he burner gratastioned in a horizontal plane within the furnace rebox n'parallelrelation.

The operation is as follows:

.i The burnermechanlsms lare installed on 45 the exterior ofy thefurnace 4with theburner igrate positioned within the fire box of thefurnace.. To start the device thegas from the gas "main 26 is turned onand the preheatep lgrate is lighted with a match or taper through. the.housing opening 27. After the`\prehea'ter grate has burned for a l toheat the primari7 vaporizer he vrimary blower 42. The valve handle iasair valve 43 so that the blower 42 will force a .desired ,volume of airthrough the air.' duet andi-the Venturi tube 46. I "uel flows' bygravity. plus a very lo\ v air, pressurefrom the oil fuelltank v12through the pipe 51 and into the nozzletube 47, the cut-off valvethrough the duct turi 4tube 46 at an increased thereby opened.. Airpassing of course 'bein i5 passes through the Ven-` nozzle 8. 'passesinto the Aheated mainvaporizer 25' vand `lsvaporized and passes'upivardl-vv 79 are posieen adjusted vpreviously tov open thev `making apressure Vdepression below atmosphere. which condition tends to drawliq- Iuid fuel Ufrom the end' of the nozzle 47.` The fuel drawn into theVenturi.

"the 'heated condition of the .vaporizeiu`v The vaporized fuel mixturefrom the Yvaporizer 19 flows into the'- primary"burnergrate 2l andleaving through the apertures-221s 1g nitedby the gas flames froni thepre-heater l25.A

The fuel "mixture from the-vaporizcr 1:9 also, floivs into the grate 29and out through the 'al'ie'rtu'res Il() and through the pipe f4() ont ofih'cv'pilot burner 39.. The

grate729 'is lighted vwith `a` taper or torch through thc housingopening 3l.` rlibe pilot burner is lighted b v ataper or torch throughthe middleop'cning in'thcstrikc plaie 3T".

The prcheater 25is nowturned oil leaving the giatel burning. The.`auxiliary grate 29'is providedlo give suflcient heat' on the bottomofthe main v'aporizer-fil to v ap'orize.

`any liquiilcollccted therein. The main viiporizer .33 is thusheatedvand the n'iuin molor\ 2 is started. The main blower 31's thus operatedtov force air-tl'iroug'h thev air duct 4 and then through theVenturi'tuhe7 4at au increased speed to draw liquid fuel f rom the'Ihemixturecf airand fuel thus through thellue` 34k and outV through theburner grate l plate '38 at a velocity 'greater than the rate of` flamepropagation. The fuel mixture escaping from theburner plate 3H isignitedb v Ithe flame from the pilot 39. The flamesi'fromfthe 'burner grate 38act as thclmain source of heat for the furnace and house. i

x'lo shutgo'i 'the main burner 38, the shu1- oft valve 13 is firstclosed and thenafter a short time, about one-half of a miuuteQthc main.blower 3 andthe main motor 2 are stopped. '[his'procediire is veryimportant Since it" eliniinatcsfall back lire. B v this Vmethod thel'uclmixture becomes so tliiu 'slowerlthairthe rate of flame propagatibn.

The main burner is stopped and*y starts autoniatlcally by a thermostaticcontrol not'.

shown in drawings. On cold nights,V the grates 21 and 29 mayl beleftburning all night. y,Onmild nightsythegrates 2l and 29 maybe turned otby closing the cut-off valve 50, and a moment later shutting oil themotor 41'.. When this is done; thepreheater ,"rnust be used to againstart the device.

The-,housing 18 which encloses the vaporizers 19 and 33 acts as' ajacket and serves to 'retain the heat aroundbthe lvaporizers topoi-ization of the fuel mixture'entering the metal. Thee-liuc 23 servesthe double purpose of carryingthe heat from the grates 21, 25 and 29 tothe furnace and preheating the metallic parts 34, 35, 36 and 38 so thattheffuel vapor will net condense onv a cold surface.

It will be noted that a cold mixture of air and fuel is delivered intothe va orizers and is directed tangentially against t ie innerpcripheral walls of the vvaporizers in such a manner that the largerparticles of fuel strike the heated walls ofthe vaporizers and l arerapidly vaporized before passing frein the vaporizers into therespective grates or burners.

The air pressure pipe 17 connecting the fuel tank withtlie airduct 45serves to 'in' crease the air pressure in the tank 12 .above atmosphericpressure with the result that the fuel from the tank will flow throughthe nozzles with greater force to beinixed with.

the air passing through the Venturi tubes..

The operation of the multiple type of burner mechanisms illustrated inFigures 6 and -7 is' similar `to .that already described.

In this case, however, a plurality of sec-v ondary blowers are provided'operable through individual control elutchesj from the motor 52.Eachfair duct .Gais-equipped."

with a separatecontreljvalve 67 and-a sepature to the separate secondaryva orizers auxiliary grates 76 are so positioned that one will causelighting of the other."

Itwill'be noted that this invention--pro- .bin-ner In said vlas't-imentioncd burner grate,

vides aincthod of heating houses and-jthe' like b vusing inconnectionwith afu'rnacea liquid'fuel burner mechanism which IS'I- adapted to beinstalled on the exterior of the furnacev with the exception. of theburner gratos which are positioned in the tire box of the' furnace. Themethod referred. to

bricfiy consists inprehc'ating an enclosed vaporizer into which a coldtfuel mixture of air andoil is directed with force after passing througha Venturi tube orearbiireter through which air is forced byl a blowerand into which oil from ay low pressure oil tank is drawn either. atatmospheric pressurefor slightly1 higher. The fuel mixture .1s directcdA into the heated vaporizer and is vaporized, passing into burner gratoswhich are ignited by the pi'elicater or by hand and" serves to continueto heat the vaporizer and also act -to heat one or more secondaryvaporize'rs, each of which has' a furnace burner grate connectedtherewith and is in'- de'pendently supplied with a cold xnixture of airand oil-'which is to be heated and vaporized to'form a fuel mixturefornsein the..

furnace burner grates to cause the furnace purpose :limiting the .patentgranted other wise than necessitated by the prior art.

I claim as iny invention:

1. A' liquid fuel'burner comprising a niotor, a blowerconnected to bedriven thereby, a. valve controllingthe entrance of air int-o saidblower,` an vair duct connected with the blower, a liquid fuel tank, aVenturi tube forined'in saidlair duet, a valveI controlled nozzleprojectinginto'said Venturi tube, a

pipe coi'inecting saidv nozzle with said tank with a cut-oft1valve'iusertcd in said pipe, an

air vprc'ssu'refpipc.Connecting said tank with said air duct, a housing,a iue foi-ined there, on,a'pr1i'i'iary vaporizer casing 1n said housjing to which the air duct is connected, a prehcater in'said housing forinitiallv heating vthc primary vaporizer, a plurality of burnergratesiconnccted with said vprimary va-poi'izcr'to receive a fuelinixture'therefrom, 'a 'secondary vaporizer casing in saidliousing'adapted to be heated by one of said burner gratos, means.connected with said sol niixturethereto to he vaporized, aI pipe con-4nccted to said secondarv vaporizerand pro- `iecting through said fine, aburner grate conneet'cdfto the' end of said pipe,' 'al pilot 2i liquid:fiiel'buriitg device comprising a housing having'v a thie, 'primary andsecondary vaporizer lcasings in said housing, a main burner grateconnected with the sec ondary i-aporizer casiiig`,a plurality ofauxiliarly burner gratos connected with the primary 'vaporizery casingfor heatinfr said vaporize casings, a preheatcr lin said housing forinitially -heating the primary vaporizer casing, air ducts connectedwithsaid va- 'porzer casing, Venturi tubes foi-ined in said air'diicts,liquid fuel nozzles projecting into said Venturi tubes, meansfor'supplying a liquid fuel to. vsaid nozzles, andmechanisin connectedwith said air ducts for-forcingair through said'air ducts andVenturitubcs to cause the .air to be carburet'ed withl the liquid fuelfrom the nozzles to forina fuel mixture ladapted to -be vprojected intosaid vaporizer casings andvaporized.

3. A `liquid fuelburner device comprise, ing a' hoiising, pr" "aryand-main vaporizer 'iliary burner grates and in said main burner grate.

4. A liquid fuel burner device comprising a housing, vaporizers in saidhousings, burner grates in said housing connected with said vaporizers,a preheater in said housing for initially heating the vaporizers, airducts projecting into the housing and connected with said vaporizors',Venturi tubes formed in said air ducts, means connected with the airducts to force air therethrough and through the Venturi tubes, and meansfor feeding a liquid fuel into said Venturi tubes to carburete the airpassing therethrough to form a fuel mixture adapted to be vaporizcd insaid vaporizers to form av vaporized fuel mixture adapted for use insaid burner grates.

5. A liquid fuel burner device `comprising a housing, vaporizerstherein, burner grates connected with said vaporizers, a preheater insaid housing for initially heating said vaporizers, air ductsconnected-with said vaporizers, restricted tubes forming a part of said'air ducts, valve controlled means connected with the air ducts to forceair Jtherethrough and through said restricted tubes, liquid fuel nozzlesprojecting into 22 said restricted tubes, valves in said nozzles,

and means connected with said nozzles for supplying liquid fuel thereto.

G. In a liquid fuel burner device, the combination with a housing, of aplurality of vaporizers therein, a preheater in said housing forinitially heating one of said vaporizers, a burner grate connected tosaid vaporizer adapted to be lighted by the preheater, burner meansconnected to said vaporizer also adapted to be lighted by hand to causeheating of the remaining vaporizers, and mechanisms for supplying a coldmixture of air and .liquid fuel to the vaporizers to be` vaporizedtherein to form va orized fuel mixture.

. In a liquid fuel burner device,the combination with a housing, ofprimary andmain vaporizers therein, a preheater in said housing forinitially heating the primary vaporizer, burner grates connected withthe primary vaporizer, mainburner grates connected with said mainvaporizers, restricted air ducts connected with said primary and mainvaporizers, means for feeding a liquid fuel into said restricted airducts, and means for forcing air 4through the restricted air ducts to becarbureted with the li uid fuel and then pass into the primary ansecondary vaporizers to be heated and vaporized to form a heatedvaporized fuel mixture for use inthe burner grates connected .with thevaporizers. v v

8. A liquid fuelburner device comprising a plurality'of vaporizers,burner grates t erefor, constricted air ducts connected with saidvaporizers, liquid fuel nozzles projecting into said air ducts, fuelpressure means connected withsaid nozzles to supply liquid fuel thereto,valve controlled blowers connected with said air ducts, and means for oerating the blowers to cause the same to force air through the air ductsto be carbureted with the liquid fuel and then pass into the vaporizersto be vaporized to afford a fuel mixture for use in the burner grates. I

In testimony whereof I have hereunto subscribed my name in the presenceof two subscribing witnesses:

" WILLIAM B. EWING.

lVitnesses:

MARY BUTLER, WV. A. WHITMAN.

'a heated

